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College Physics Department Research Experiences for Undergraduates Summer 2007 Project Summary |
| Project Title: | Millisecond Pulsars and Their Profiles |
| Student Name: | Sonal Patel |
| Student's Home Institution: | Rutgers University, New Brunswick |
| Research Advisor: | Dr. Peter Gonthier |
| Source of Support: | This material is based upon work supported by the National Science Foundation under NSF-REU Grant No. 0452206 and NSF-RUI Grant No. 0307365 and the NASA-Astrophysics Theory Program. |
Modeling pulsar pole emissions as two Gaussian beams, a core and a cone, enables us to constrain the viewing geometry of millisecond pulsars and estimate their magnetic inclination and impact angles. We fit the profiles of millisecond pulsars found on the European Pulsar Network database. When good polarization data is available we also fit the position angle sweeps of the millisecond pulsars using the rotation vector model, allowing us to find the maximum rate of position angle sweep. We can then constrain the magnetic inclination in order to determine the impact angle. Fitting these pulsars for multiple frequencies allows us to more accurately estimate the viewing geometry. We can then incorporate the beam geometry into pulsar population models and determine the number of observable and unobservable pulsars.